195777381 has 4 divisors (see below), whose sum is σ = 261036512. Its totient is φ = 130518252.

The previous prime is 195777371. The next prime is 195777391. The reversal of 195777381 is 183777591.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 183777591 = 3 ⋅61259197.

It is an interprime number because it is at equal distance from previous prime (195777371) and next prime (195777391).

It is not a de Polignac number, because 195777381 - 2²¹ = 193680229 is a prime.

It is a super-2 number, since 2×195777381² = 76657565822438322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 195777381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195777301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32629561 + ... + 32629566.

It is an arithmetic number, because the mean of its divisors is an integer number (65259128).

Almost surely, 2^195777381 is an apocalyptic number.

It is an amenable number.

195777381 is a deficient number, since it is larger than the sum of its proper divisors (65259131).

195777381 is an equidigital number, since it uses as much as digits as its factorization.

195777381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65259130.

The product of its digits is 370440, while the sum is 48.

The square root of 195777381 is about 13992.0470625281. The cubic root of 195777381 is about 580.6585672390.

The spelling of 195777381 in words is "one hundred ninety-five million, seven hundred seventy-seven thousand, three hundred eighty-one".